Unfortunately myco75 I was unable to test them out side by side.
I was about ready to buy a sub when I decided that I would just give the T6s another shot. I went back to the shop where they were on sale and asked the same individual (the owner) if I could buy the T6s, and what their return policy was - he was a bit colder than the day before and told me they would not accept returns. I asked if I could perhaps demo the floor models in my own space and he said no.
Originally I was there on the 26th and when I returned on the 27th he had assumed I returned the RTI A9s but once I told him I had not he seemed unwilling to help me out.
So I thought I'd give another listen to the T6s anyway since I was there. For the same price as the A9s I thought they sounded excellent as well, however I think that the A9s have slightly more crispness to them, but the T6 had bit more oomph, although it was hard to tell not hearing them back to back, instead I heard them before the A9s, then again after the listening to the A9s. I decided against the T6s for 2 reasons, 1 I really like the crispness that the A9s provide and for more bass I can add an amp or a sub - whereas the T6s did not come across as sharp (though still very clean sounding) the room I listened to them in was also much smaller and more compact with certain materials for better sound reproduction for the extra "oomph". And 2 I wasn't too impressed with the owners lack of help. I understand he wants to make money, but his unwillingness to find a solution other than telling me that the T6s sounded better just didn't work for me. I couldn't risk buying the T6s being unable to return them, especially since I already knew the sound from the A9s was excellent and very much to my liking.
I don't feel I'm missing out, I think I would have been happy with either speaker, they both sound fantastic, clear and layered, but in the end it's easier for me to add more power to my A9s than to get the clarity I want from the T6s.
If you can demo them both Myco75 then take advantage of that because perhaps the rounder sound of the T6s is more to your liking, but I don't think you can go wrong with either speaker, these are both great speakers to my ear and most would be happy with either one.
For the record, I was able to play both speakers through the Yamaha R-S500.
Also an update: after I returned from the shop I decided to test the PSB Alpha Subseries 1 (that my parents use for their home theater) with my A9s and it sounded great. Although it's still not the type of sub I would use as it's less for music and more for home theatre, it's still closer to the sound I am looking for. I'm definitely not feeling any buyers remorse with these A9s and I look forward to how I can push them further.
Thank you to those who gave me their input and thank you ack_bk for mentioning how to adjust the sub. Although I haven't decided on a sub yet I have a much better idea of the sound I can get utilizing the crossover of the PSB sub with the speakers.
Edited by EndoftheDream - 12/28/13 at 7:40pm